A bad timing chain that is not allowing the camshaft to operate properly to open and close the intake valves like they should could cause your engines compression to be low.
Your engine would be misfiring and possibly be hard to start up as well if the timing chain is bad.
Another cause of low compression is worn piston rings, head gasket failure or bad or warped cylinder heads.
You can run a compression test on the engine and see if your engine has the proper compression and if not then it could be a head gasket issue, piston rings worn out or even yes the timing chain.
Your timing could be off not allowing the proper compression but if it's not the timing chain then it could be your head gasket, warped or cracked heads, or worn piston rings.
Your intake valves may not be sealing properly as well or you may also have broken valve springs that could be causing the low compression.